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What could explain the gallium anomaly?

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Re: What could explain the gallium anomaly?

#11

Post by Etheryte »

dylan604 wrote: post #6
CamperBob2 wrote: post #2

Photo caption: In the lab that houses the BEST experiment, fish serve as an early warning system about any leaking radiation. Never change, Russia. Never change.

You can't get them all right. To be fair, they used pencils while NASA spent time and money to have a pen that writes in 0g.

This is a myth, using a pencil in space isn't clever or thrifty, it's a disaster waiting to happen. The graphite from pencils breaks off in small fragments while writing and the fragments can create shorts in electronics and to top it off they're also flammable. None of those are properties you want to bring into a spacecraft.

Re: What could explain the gallium anomaly?

#12

Post by AnimalMuppet »

ars wrote: post #3

Would sterile neutrinos as an oscillation really change anything about dark matter? The total mass of neutrinos doesn't change, just the lepton number.

It might mean 20% more neutrinos exist than we think. That would change the total mass of neutrinos.

Much more interesting (and not touched on by the article as far as I noticed): The electron neutrino is the "partner" to the electron. The muon neutrino is the partner to the muon, and the tau neutrino to the tau. What's the sterile neutrino the partner to? (Or doesn't it have one, and that's what makes it "sterile"?)

If there is a partner to it, does the partner have mass? Does it interact in any way besides gravitationally? If not...

Re: What could explain the gallium anomaly?

#13

Post by torrefatto »

AnimalMuppet wrote: post #12
ars wrote: post #3

Would sterile neutrinos as an oscillation really change anything about dark matter? The total mass of neutrinos doesn't change, just the lepton number.

It might mean 20% more neutrinos exist than we think. That would change the total mass of neutrinos. Much more interesting (and not touched on by the article as far as I noticed): The electron neutrino is the "partner" to the electron. The muon neutrino is the partner to the muon, and the tau neutrino to the tau. What's the sterile neutrino the partner to? (Or doesn't it have one, and that's what makes it "sterile"?)…

IIRC, there is another quantum number, the chirality. All the neutrinos measured are left chiral. The sterile neutrino, which does not pair with other lepton, is right chiral.

Re: What could explain the gallium anomaly?

#14

Post by mrguyorama »

dylan604 wrote: post #6
CamperBob2 wrote: post #2

Photo caption: In the lab that houses the BEST experiment, fish serve as an early warning system about any leaking radiation. Never change, Russia. Never change.

You can't get them all right. To be fair, they used pencils while NASA spent time and money to have a pen that writes in 0g.

After Fisher, the pen company, spent their own couple millions to develop a pen that could write in zero gravity, they convinced NASA to use it, and a few years later the Soviets bought 100 of them for their own space program.

NASA was never involved in the development of the space pen, though they supposedly had their own effort that was quickly abandoned as it got expensive. Before that they also used pencils.

The pen is just a better writing implement in space. It cost $3 in the 60s, with wide availability.

Re: What could explain the gallium anomaly?

#15

Post by PaulHoule »

ars wrote: post #3

Would sterile neutrinos as an oscillation really change anything about dark matter? The total mass of neutrinos doesn't change, just the lepton number.

Sterile neutrinos could also be a lot heavier than regular neutrinos, those kind of sterile neutrinos are ideal candidates for explaining dark matter and the matter-antimatter asymmetry

https://arxiv.org/abs/1303.6912

Just as I am disappointed that "global warming" changed into the more ambiguous "climate change", I'm a little disappointed that the "right-handed neutrino" has turned into the "sterile neutrino". It's really strange that we only observe left handed neutrinos and either the revelation that there is a hidden right-handed neutrino or that neutrinos are fully Majorana particles without a right-handed form would be absolutely groundbreaking.

My take on it is that the neutrino mass term is not "physics beyond the standard model" but rather a "missing part of the standard model" and that one way or another, neutrinos hold an important secret, if not the important secret of the universe. (Note potentially three generations of right-handed neutrinos could exist at three mass scales and explain the gallium anomaly, cold dark matter, and the rarity of antimatter)

Re: What could explain the gallium anomaly?

#16

Post by addaon »

Terr_ wrote: post #4

> sterile neutrinos It's funny when one encounters serious real-world discussion on something previously seen as sci-fi technobabble. In this case, I'm thinking of the Destiny universe, such as this apocalyptic alert from a military AI. [0] > Multiple distributed ISR assets report a TRANSIENT NEAR EXTRASOLAR EVENT. Event duration ZERO POINT THREE SECONDS. Event footprint includes sterile neutrino scattering and gravi…

Google is (still) a great tool for this sort of conversion. It comes up with just under 58 barrels: https://www.google.com/search?q=57+tonnes+%2F+%286.1+g%2Fcm%...

Re: What could explain the gallium anomaly?

#17

Post by AnimalMuppet »

torrefatto wrote: post #13
AnimalMuppet wrote: post #12

Earlier quoted context omitted.

It might mean 20% more neutrinos exist than we think. That would change the total mass of neutrinos. Much more interesting (and not touched on by the article as far as I noticed): The electron neutrino is the "partner" to the electron. The muon neutrino is the partner to the muon, and the tau neutrino to the tau. What's the sterile neutrino the partner to? (Or doesn't it have one, and that's what makes it "sterile"?)…

IIRC, there is another quantum number, the chirality. All the neutrinos measured are left chiral. The sterile neutrino, which does not pair with other lepton, is right chiral.

Is that the only possible sterile neutrino? Because if I recall correctly, a right chiral neutrino cannot change into one of the other types, because of the chirality. (That's why it's "sterile".)

So either they aren't produced by beta decay, or they are but they can't be captured by gallium, or we're seeing a sterile neutrino in a different sense. ("Sterile" because it can't interact with gallium, but not sterile due to chirality.)

If I understand, the conversion of gallium into germanium is exactly a beta interaction. (But I may not understand, because it seems to me that gallium->germanium should emit a neutrino, not absorb one.) So I have a hard time seeing how a neutrino could be emitted by the source, but not absorbed by gallium. I could more readily see it as saying that there's a fourth type of neutrino that they cycle through, and while in that fourth state it can't convert gallium. But that wouldn't be "sterile" in the chirality sense.

Re: What could explain the gallium anomaly?

#18

Post by ars »

AnimalMuppet wrote: post #12
ars wrote: post #3

Would sterile neutrinos as an oscillation really change anything about dark matter? The total mass of neutrinos doesn't change, just the lepton number.

It might mean 20% more neutrinos exist than we think. That would change the total mass of neutrinos. Much more interesting (and not touched on by the article as far as I noticed): The electron neutrino is the "partner" to the electron. The muon neutrino is the partner to the muon, and the tau neutrino to the tau. What's the sterile neutrino the partner to? (Or doesn't it have one, and that's what makes it "sterile"?)…

> It might mean 20% more neutrinos exist than we think.

Would it though? It's not like we know neutrino mass from measurement, rather we estimate it from nuclear reactions that have occurred. The estimate would not change if a neutrino oscillates into a sterile one.

Re: What could explain the gallium anomaly?

#19

Post by ars »

AnimalMuppet wrote: post #12
ars wrote: post #3

Would sterile neutrinos as an oscillation really change anything about dark matter? The total mass of neutrinos doesn't change, just the lepton number.

It might mean 20% more neutrinos exist than we think. That would change the total mass of neutrinos. Much more interesting (and not touched on by the article as far as I noticed): The electron neutrino is the "partner" to the electron. The muon neutrino is the partner to the muon, and the tau neutrino to the tau. What's the sterile neutrino the partner to? (Or doesn't it have one, and that's what makes it "sterile"?)…

> What's the sterile neutrino the partner to?

It would be a very unusual partner that has no concerved quantum numbers, and only mass.

A sterile neutrino would also imply that the neutrino is a Majorana particle (because it would have not quantum numbers that could be "anti").

Re: What could explain the gallium anomaly?

#20

Post by Terr_ »

addaon wrote: post #16
Terr_ wrote: post #4

> sterile neutrinos It's funny when one encounters serious real-world discussion on something previously seen as sci-fi technobabble. In this case, I'm thinking of the Destiny universe, such as this apocalyptic alert from a military AI. [0] > Multiple distributed ISR assets report a TRANSIENT NEAR EXTRASOLAR EVENT. Event duration ZERO POINT THREE SECONDS. Event footprint includes sterile neutrino scattering and gravi…

Google is (still) a great tool for this sort of conversion. It comes up with just under 58 barrels: https://www.google.com/search?q=57+tonnes+%2F+%286.1+g%2Fcm%...

> Google is (still) a great tool for this sort of conversion

Alas, not in this case, since Google is interpreting that as a 42-gallon "petrochemical-industry traditional abstract measuring unit of crude oil" as opposed to a 55-gallon "physical container readers may have seen and everybody actually uses." (Including to hold crude oil, in the rare cases that it's not in an enormous tank or pipeline.)

Perhaps this is an example of where "intelligent assistant" software lands in a dangerous middle-zone of "wrong, but not wrong enough that it's obvious."

Anywho, if we reword it a bit and put in a less-rounded density, it comes out the same:

https://www.google.com/search?q=57+tonnes+%2F+%286.095+g%2Fc...

__________

P.S.: The way it parses this small change is also amusing, where "in water barrels" isn't a change in the type of barrel, but instead introduces a non-SI unit of pressure, making everything murky indeed.

https://www.google.com/search?q=57+tonnes+%2F+%286.1+g%2Fcm%...

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